1. The DC protection can't work with the Digital Power Amplifier board or BTL Circuits 2. The horn protection board has the functions of power-on delay (about 3 seconds) and DC protection (control voltage is about 1V). The board circuit is simple and safe and reliable. 3. With LED light indication, it lights up when working, and it is extinguished when protection starts. It adopts double parallel OMRON relay, which is suitable for most power amplifier boards. 4. This protection board is powered by AC 12-18V.It must be powered by a separate power supply. Otherwise, the power amplifier board may be damaged. Can withstand power: 50W-300W Protection board size: 68 x 55 MM Maximum Power Per Channel: 101-130W Model Number: UPC1237 Channels: 2 (2.0) Type: Home Amplifier color:Photo color Material:ABS Package Contents: 1 x Speaker Protection Board Only the above package content, other products are not included. Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.